scope:

Description of Driving Event:

The orbiter/ET feedline mating stud tensioner unit exposes personnel to a high pressure source and could result in injury or flight hardware damage. During ratcheting of the nut onto the stud, personnel will be in the vicinity of high-pressure fluid, water, and rust inhibitor at 11,600 psig. Three stud tensioner heads, connected by six hoses through a common manifold, are used to apply a tension load of 64,000 lbs maximum to three cryogenic umbilical separation bolts by means of an air-driven hydraulic pumping unit.